Refactor OWNERS in platform/prebuilts/build-tools am: 0a2bd86863 am: f0d1a5f110 am: 7b6f1c117f am: f4193e8be8

Original change: https://android-review.googlesource.com/c/platform/prebuilts/build-tools/+/1455795

Change-Id: I6bcfa76abcaf46907d4cd5e5419c42650add952c